08-25-2021, 08:07 PM
Check the alternator output not just at the starting battery but more importantly at the bank to be charged. You might find that line loss takes care of any high voltage issues. You will need a converter such as a DC to DC charger if it's too high because isolators only use voltage to turn on and off. Even the lithium built BIM 225 will only stop charging if the alternator voltage gets too high. It's advantage over a DC to DC charger is that it uses timed intervals of charging and not charging to allow the alternator to cool down.
Only once have I seen the voltage from a alternator too high and that was for a instant before the voltage regulator kicked in. Cheap charge controllers will allow the voltage to climb too high during cloud effect for seconds before they cycle and knock it back down. Long enough to shut down a inverter due to the voltage going over 15 volts.
Remember that the purpose of the BMS is to keep the battery from being smoked.
Only once have I seen the voltage from a alternator too high and that was for a instant before the voltage regulator kicked in. Cheap charge controllers will allow the voltage to climb too high during cloud effect for seconds before they cycle and knock it back down. Long enough to shut down a inverter due to the voltage going over 15 volts.
Remember that the purpose of the BMS is to keep the battery from being smoked.
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